Reversible variable pitch propeller for boats



March 1955 G. J. DANIELSON 2,704,991

REVERSIBLE VARIABLE PITCH PROPELLER FOR BOATS Filed May 8, 1953 3 Sheets-Sheet l I N V EN TOR. Gus 777 HE J. 0flN/ EL :oN

March 29, 1955 G. J. DANIELSON REVERSIBLE VARIABLE PITCH PROPELLER FOR BOATS '3 Sheets-Sheet 2 Filed May 8, 1955 9 NT mm v K8 9Q bv Rm 5 Ma m0 J E V m U 6 March 29, 1955 G. J. DANIELSON REVERSIBLE VARIABLE PITCH PROPELLER FOR BOATS 3 Sheets-Sheet 3 Filed May 8, 1955 v INVENTOR. Gusmuf J Dav/u so United States Patent REVERSIBLE VARIABLE PITCH PROPELLER FOR BOATS Gustave J. Danielson, Seattle, Wash.

Application May 8, 1953, Serial No. 353,861

3 Claims. (Cl. 115-34) This invention relates to improvements in propellers for boats and it has reference more particularly to the details of construction of a reversible, variable pitch propeller of a type especially adapted for the propulsion of pleasure boats and fishing boats, although not to be limited to boats of any particular kind or to boats of any particular size; it being the principal object of the present invention to provide a propeller of the above character that can be positively and accurately adjusted and controlled; that can be quickly and easily adjusted to any position of use between its opposite limits as provided for forward or rearward propulsion; that is strong and durable in its construction, and is relatively inexpensive to manufacture.

Further objects of the invention reside in the details of construction of the various parts, in their combination, and in their mode of operation, as will hereinafter be fully described.

In accomplishing these and other objects of the invention, I have provided the improved details of construction, the preferred forms of which are illustrated in the accompanying drawings, wherein Fig. l is a side view of the stern end portion of a boat that is equipped with a reversible variable pitch propeller embodying the improvements of the present invention therein.

Fig. 2 is a cross-section taken substantially on line 2--2 in Fig. 1, showing the bracing members associated with the propeller.

Fig. 3 is a central, longitudinal section of the propeller blade mounting housing and the mechanism contained therein for making adjustments of the propeller blades.

Fig. 4 is a cross-section taken on line 4-4 in Fig. 3.

Fig. 5 is a cross-section taken on line 5-5 in Fig. 3.

Fig. 6 is a perspective view showing relationship of the propeller blades and part of the blade adjusting mechanism; these parts being removed from their housings for explanatory purposes.

Referring more in detail to the drawings- In Fig. 1, 10 designates the stern end portion of a boat, 11 designates the rear end portion of the keel, and 12 designates the boats rudder. A propeller driving shaft 13, operated by the boats power plant which is not herein shown, extends rearwardly through a stufiing box 14 in the keel and 15 designates, in its entirety, the propeller of the present invention as mounted on the propeller shaft for driving thereby.

As best shown in Fig. 3, the propeller mechanism comprises a hollow and substantially cylindrical housing comprising forward and rearward end portions, 16 and 20. The forward end portion 16 is closed at its forward end and is there keyed to the propeller shaft by keys designated at 1717. The cylindrical rear end portion of the housing 16 is fitted for rotation about the forward end of the rear end portion 20, which also is hollow and to which the lower ends of a pair of upwardly diverging, tubular brace struts 2121 are fixed. At their upper ends, these struts are securely fixed to the boat bottom 22, as shown in Fig. 2. It is through these tubular struts that an operating connection is made with the propeller for effecting pitch adjustment of its blades, as will presently be described.

The housing 16 serves as the hub portion of the propeller, and the propeller shaft 13 has a portion 13a of reduced diameter extending coaxially within the hub portion 16 to terminate in a further diametrically reduced end portion 13b; this latter portion being revolubly contained in a pair of antifriction ball bearings 2525' that are fitted in the forward end portion of the non-rotatable housing 20. The raceways for these bearings are located at opposite sides of a transverse partition wall 26 that is integral with the hollow housing 20, and a circular disk 27, fixed to the end of shaft 13 by a center screw 28, engages the bearing 25 in such manner as to hold these parts functionally in the relationship in which they are shown in Fig. 3. It will be understood by reference to Fig. 2, that the housing 20 is held rigidly against rotation by the bracing struts 21 and 21 which are fixed thereto and to the boat bottom, while the propeller, including hub and blades thereon, revolves with the propeller shaft 13. Packing, as at 29, is applied within grooves that encircle the forward end portion of housing 20 to seal the joint that is between the overlapped parts of housings 16 and 20, as noted in Fig. 3.

The propeller blades 15x, here shown to be three in number, are equipped at their inner ends with short mounting journals 32 revolubly contained in bearing portions 16x of the hub 16, as shown in Figs. 3 and 5. Fixed on the inner ends of the three journals 32, which are equally spaced about the hub and extend radially therefrom, are propeller adjusting lever arms 33, arranged about the propeller drive shaft 13, as shown in Fig. 5.

Each lever arm 33 has a short stud 34 fixed in its outer end portion and these studs are slidably contained in grooves 35 that are formed transversely across posts 36 that are fixed to a propeller adjusting collar 38 contained coaxially within the hub 16 and slidably adjustable along the diametrically reduced end portion 13a of the propeller shaft 13. It is shown in Figs. 5 and 6 that the posts 36 are parallel with and equally spaced about the shaft 13, and that each of the lever arms 33 is directed transversely across the corresponding post 36. Thus, the shifting of the collar 38 along the propeller shaft equally and simultaneously rotatably adjusts the pitch of the three propeller blades 15x. This adjustment may be such as to change from forward to reverse propulsion, or to bring the blades to a neutral position for idling.

The adjustment of the collar 38 along the shaft 13 as required for change in pitch or direction of propulsion, is effected by the following means:

Mounted in the housing 20, and held therein against r0 tation and endwise movement, is a bearing block 40 that, in coaxial alignment with the propeller shaft, is formed with a circular opening 41 within which the hub portion 42H of a sprocket wheel 42 is rotatably fitted. The sprocket wheel 42 is mounted to rotate substantially in the plane of the axial lines of the two brace struts 21-21 as shown in Fig. 3. A plug 43 that is fitted and secured in the rear end portion of the housing 20 retains the sprocket gear wheel 42 against displacement from the bearing 40, as will be understood by reference to Fig. 3.

Threaded coaxially through the hub and body of the sprocket wheel 42 is a shaft 45 that is fixed at its forward end in the center of a crosshead block 46. Fixed to the cross-head block 46, at diametrically opposite points relative to the shaft 45, are the rear end portions of a pair of links 47-47, which links, at their forward ends are attached to a slip ring 48 that is contained in an encircling groove 49 in the hub portion 38h of the collar 38. These links 4747 extend freely through openings 50-50 formed through the partitioning Wall 26 in the housing 20, and extend parallel with and along opposite sides of the shaft 13. The collar 38 is adjustable along the reduced portion 13a of shaft 13, but rotates therewith.

It will be understood that with sprocket wheel 42 held against endwise movement, rotation thereof in opposite directions will cause forward or rearward shifting of the shaft 45, and this, in turn, will cause a corresponding forward or rearward shifting of the block 46 and links 4747, to adjust the collar 38 forwardly or rearwardly and thereby effect the rotary adjustment of the propeller blades by reason of the oscillating action transmitted to ihtlel lever arms 33 by the posts 36 which move with the co ar.

The adjustment of the propeller blades and the securement of their position of adjustment is effected through the mediacy of a sprocket chain 60 that is applied about the lower part of the sprocket wheel 42 as seen in Figs.

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3 and 6. The opposite end portions of the chain extend from the sprocket wheel, upwardly through openings as at 61, in the housing 20 and lengthwise through the tubular struts 2121, thence over guide sheaves 65-65, as in Fig. 2. Suitable cable 67 extend from the ends of the chain to the drum 70 of a cable winding device designated at 71 in Fig. 1. The turning of the drum by hand crank or other means, will cause the opposite ends of the cable or chain to be wound onto and paid out from the drum to rotate sprocket wheel 42 and thus effect the forward or rearward shifting movement of the collar 38 that is necessary to effect the desired pitch adjustment of the propeller blades, for forward or rearward propulsion, or to place them in a neutral setting as for idling.

A lubricant can be fed into the hollow housing 20 and hub 16 through a longitudinal channel 75 provided in one of the brace struts 21 as has been shown in Fig. 3.

By the means above described, the pitch adjustment of the propeller blades can be quickly made, and can be retained. The mechanism is substantial, reliable, long wearing, easy to assemble or disassemble and so designed that it in no way interfered with the efficiency of the propeller.

Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is:

1. In a boat having a rotatably driven propeller shaft; a hollow housing mounted coaxially on the end portion of said shaft comprising coaxially associated forward and rearward portions; the forward of said portions being fixed to said propeller shaft for rotation therewith, a strut connecting the rearward portion with the boat hull and holding it against rotation, a plurality of propeller blades functionally mounted on the rotatable portion of said housing, each blade having a mounting journal extended through the housing wall to the interior thereof, lever arms fixed radially to said journals at their inner ends, a blade adjusting member contained in the housing and movable lengthwise thereof in opposite directions; and having operative connections with said lever arms for effecting simultaneous and equal rotative adjustment of the propeller blades between forward and rearward propelling positions, a screw mounted axially within the nonrotative portion of the housing and having a holding connection at one end with the blade adjusting member for its actuation, a nut threaded onto the shaft, means in the housing retaining the nut against shifting in its axial direction, and means extended to the nut through said strut and operable to effect its rotation for propeller adjustment.

2. A mechanism as recited in claim 1 wherein the blade adjusting member includes a collar that is mounted in the housing for sliding travel along the shaft and equipped with individual connections with said lever arms, a cross-head in the housing, links connecting the crosshead with the collar for shifting it, a screw shaft fixed at one end to the cross-head, a nut threaded onto the screw, means in the non-rotative portion of the housing retaining the nut against axial shifting therein, and means extended into the housing through said strut for rotating said nut for effecting endwise movement of the screw shaft for making propeller blade adjustment.

3. In a boat having a propeller shaft, a hollow housing mounted on the end portion of said shaft, comprising coaxially aligned forward and rearward end portions, the forward portion being keyed to the shaft for rotation therewith, a pair of tubular struts fixed to the rearward portion and to the boat hull and providing passages therethrough opening into the boat hull and into the housing, propeller blades mounted on the rotatable portion of the housing, each having a mounting journal extended through the housing wall to the interior thereof, lever arms fixed radially to said journals at their inner ends, a shaft bearing fixed in the housing between its ends and containing the inner end of the propeller shaft therein, a collar slidable in said shaft at one side of said bearing, a cross-head movable longitudinally of the housing at.the other side of the bearing, said bearing having passages therethrough and there being links passing through said passages and joining the cross-head and collar for shifting the latter for propeller blade adjustment, a screw shaft fixed to the cross-head and extending coaxially of the housing, a nut threaded on said shaft, means in the non-rotatable part of said housing for holding said nut against shifting lengthwise of the housing, sprocket teeth encircling the nut, a chain operating about the nut in mesh with said teeth and extended through said tubular struts, and means in the boat for shifting the chain for turning the nut.

References Cited in the file of this patent UNITED STATES PATENTS 2,133,519 Hunter et a1. Oct. 18. 1938 2,505,071 Stepanofi Apr. 25, 1950 FOREIGN PATENTS 1,855 Great Britain May 12, 1877 382,091 France Jan. 19, 1908 437,583 Germany Nov. 26, 1926 932,276 France Nov. 17, 1947 

